1. Field of the Invention
The present invention relates to an ink cartridge and an ink-jet printer having the same, and more particularly, to an ink cartridge detecting an amount of ink remaining in the ink cartridge, and an ink-jet printer having the same.
2. Description of the Related Art
In general, ink cartridges for ink-jet printers store ink, eject ink droplets through printheads and print images having predetermined colors onto paper. FIG. 1 illustrates an ink cartridge disclosed in U.S. Pat. No. 5,359,353 to Hunt et al. that detects an amount of ink remaining in a printing step. Referring to FIG. 1, a housing forming the outer wall of the ink cartridge includes a peripheral wall 10 and a pair of side plates (not shown), which are affixed to the peripheral wall 10 to enclose both sides of the peripheral wall 10. A flexible ink bag, which forms an enclosed space and stores ink, is disposed in the housing. Here, a pair of sides 11a and 11b formed of a flexible plastic material, are secured by cement or thermoplastic fusion onto inner edges 17a of the peripheral wall 10, thereby forming the flexible ink bag. Intervening metal panels 18 and 19 bear against inside surfaces of the sides 11a and 11b and are held in place by outward pressure from a double-bowed compression spring 20. Flexible strips 13 and 14 having an ink volume indicia thereon are attached at one end to the sides 11a and 11b of the flexible ink bag. The other ends of the flexible strips 13 and 14 are folded over an edge of the peripheral wall 10 and are overlapped on a space 15 formed on the peripheral wall 10. The overlapped flexible strips 13 and 14 are covered with a cover tape 24 in which a stationary window 25 is formed. Reference numeral 12 denotes a plurality of nozzles through which ink is ejected from the flexible ink bag.
In the above structure, as ink supply decreases, the sides 11a and 11b of the flexible ink bag retreat inward due to a negative pressure that increases in the flexible ink bag, causing a deformation of the flexible strips 13 and 14 connected to the sides 11a and 11b of the flexible ink bag. Thus, the ink volume indicia on the flexible strips 13 and 14 is exposed such that the amount of ink remaining is recognized through a stationary window 16 formed in the flexible strip 13 and through the stationary window 25 formed in the cover tape 24.
However, the above ink cartridge has an asymmetric structure caused by the space 15 formed at one side of the peripheral wall 10, disturbing a movement of a spring in the flexible ink bag. In addition, the amount of ink remaining cannot be recognized at all times.
Various objects and advantages of the invention will be set forth in part in the description that follows and, in part, will be obvious from the description, or may be learned by practice of the invention.
In accordance with an aspect of the present invention, there is provided an ink cartridge having an improved structure such that a user can recognize an amount of ink remaining as ink supply decreases, can simultaneously sense the amount of ink remaining using an optical sensor, and enables the user to know whether or not the ink cartridge needs to be replaced, and an ink-jet printer having the same.
In accordance with an aspect of the present invention, there is provided an ink cartridge. The ink cartridge includes an ink reservoir storing ink includes a base plate, a cover plate movable toward the base plate, and at least one flexible bag between the base plate and the cover plate; a housing having an opening that is combined with the base plate and covers the ink reservoir, and having a slit formed on a side of the housing; a panel-shaped spring disposed between the housing and the cover plate and including a housing fixing portion fixed to the housing and a plate fixing portion fixed to the cover plate; a strip having one portion that is combined with the panel-shaped spring to move when the panel-shaped spring is deformed, and another portion that is exposed to an outside of the housing through the slit of the housing, and an indicator pattern formed on a surface of the exposed portion of the strip; and a strip cover covering the exposed portion of the strip, and in which an indicator window is formed such that a user observes the indicator pattern as the strip moves.
A space having a predetermined shape, in which the exposed portion of the strip is disposed, is formed at the side of the housing in which the slit is formed. When the slit is formed at two opposite sides of the housing, both ends of the strip are exposed to the outside of the housing through the slit, and a middle part of the strip is combined with the panel-shaped spring, or one end of each of two strips is exposed to the outside of the housing through the slit, and the other end of each of the two strips is combined with the panel-shaped spring.
In accordance with an aspect of the present invention, there is provided an ink-jet printer including an ink cartridge and a carriage on which the ink cartridge is mounted. The ink cartridge includes an ink reservoir storing ink, the ink cartridge including a base plate, a cover plate movable toward the base plate, and at least one flexible bag between the base plate and the cover plate; a housing having an opening that is combined with the base plate and covers the ink reservoir, and having a slit formed on a side of the housing; a panel-shaped spring disposed between the housing and the cover plate and including a housing fixing portion fixed to the housing and a plate fixing portion fixed to the cover plate; a strip having one part that is combined with the panel-shaped spring to move when the panel-shaped spring is deformed, and another portion that is exposed to an outside of the housing through the slit of the housing, and an indicator pattern formed on a surface of the exposed portion of the strip; and a strip cover covering the exposed portion of the strip, and in which an indicator window is formed allowing a user to observe the indicator pattern as the strip moves.
The carriage includes a detecting unit which optically detects a movement of the strip through the indicator window formed on the strip cover.
Here, the detecting unit includes a light emitting portion and a light receiving portion to sense a variation in a quantity of light reflected from the strip.
In accordance with an aspect of the present invention, there is provided an ink cartridge, including: an ink reservoir storing ink; a housing covering the ink reservoir; a panel-shaped spring disposed between the ink reservoir and the housing; a strip connected to the panel-shaped spring having sides exposed to an outside of the housing movable when the panel-shaped spring is deformed; indicator patterns formed at ends of the sides of the strip to indicate an amount of ink remaining; and strip covers attached to both sides of the housing to detect the amount of ink remaining in the ink reservoir.
In accordance with an aspect of the present invention, there is provided an ink-jet printer, including: an ink cartridge including an ink reservoir storing ink, a housing to cover the ink reservoir, a panel-shaped spring disposed between the ink reservoir and the housing, a strip connected to the panel-shaped spring having sides exposed to an outside of the housing movable when the panel-shaped spring is deformed, indicator patterns formed at ends of the sides of the strip to indicate an amount of ink remaining, and strip covers to detect the amount of ink remaining in the ink reservoir; and a carriage on which the ink cartridge is mounted, the carriage includes a detecting unit optically detecting a movement of the strip through an indicator window formed on the strip cover.
These together with other aspects and advantages which will be subsequently apparent, reside in the details of construction and operation as more fully hereinafter described and claimed, reference being had to the accompanying drawings forming a part thereof, wherein like numerals refer to like parts throughout.